“I would say the importance of sleep is definitely underestimated by the general public,” said Dr. Sandhya Kumar, assistant professor of neurology at Wake Forest Baptist Medical Center and medical director of its Sleep Center. “Some people may say all they need is five hours of sleep and if they’re getting that they’re good to go, but what they’re not realizing is that they’re probably not functioning at their fullest potential.”

Sleep is much more than simple rest. The brain and body don’t shut down during sleep; rather, they perform important tasks that promote both mental and physical health, such as producing hormones that help repair cells and fight off illness. Proper sleep contributes significantly to feeling better and functioning better when awake.

And “beauty sleep” is no mere myth: A 2011 Swedish study found that “sleep-deprived people appear less healthy, less attractive and more tired compared with when they are well rested.”

Conversely, according to volumes of research, inadequate sleep can cause people to be irritable, have slower response times, make unwise decisions, have trouble with relationships, perform poorly at work or school and become depressed more easily, not to mention increasing the risk for high blood pressure, heart disease, diabetes, obesity, cognitive difficulties and other medical problems.

In fact, the federal Centers for Disease Control and Prevention, citing societal factors such as round-the-clock access to technology and the incidence of disorders such as insomnia and sleep apnea, has called insufficient sleep a public health epidemic.

The amount of sleep a person needs depends on his or her age. Generally, newborns require 16 to 18 hours nightly, preschoolers 11 to 12 hours, school-age children and teenagers at least 10 hours and adults (including seniors) between seven and eight hours.

“There are some individuals, whom we call ‘short sleepers,’ who probably will do OK with maybe only six hours, and at the other extreme there are ‘long sleepers,’ who require nine or 10 hours, but the percentage of these extremes are very small,” Kumar said. “Most of us, after adolescence, really need seven or eight hours of sleep, and on a regular basis.”But it’s not just the amount of time spent sleeping that counts. There’s a quality factor, too.

“There are people who, for example, say that they can drink coffee and don’t have trouble sleeping, but that’s not true,” Kumar said. “They may not have trouble falling asleep but the quality of their sleep is not what they need. They don’t have the deep sleep that is the most restful, or they have trouble waking up.”

The same is true with alcohol, Kumar said. “Having a drink before going to bed may help you fall asleep but the quality of sleep isn’t good, so you’re probably not going to feel rested at all the next day,” she said.

The first thing anyone who has, or thinks they may have, a sleeping problem should do, Kumar said, is examine their habits to see if they’re following proper sleep hygiene. The easiest way to do this is on the Internet, where a number of authoritative sites – Kumar recommends www.yoursleep.aasmnet.org, an American Academy of Sleep Medicine site – offer advice on ways to get a good night’s rest.

But what if following the tips – allowing sufficient time for sleep, going to bed and waking up the same time every day, removing distractions from the bedroom – doesn’t help?The next step, Kumar said, should be to see a doctor, either a primary care physician or a sleep specialist, because many sleeping problems are caused by other health or medical issues. Insomnia, for example, can be a reaction to a prescription drug, while restless leg syndrome is linked to iron deficiency.

“In most cases a primary care physician should be able to evaluate the symptoms and determine what is causing the sleeping problem and then prescribe a treatment,” she said.But that treatment shouldn’t necessarily include sleeping pills, Kumar noted.

“Prescription sleep aids can be helpful in the short term; they can help with initiating and maintaining sleep,” she said. “But taking a sleep aid and not doing anything else doesn’t help over the long term. It’s important to find the cause of the problem, not rely on a sleep aid alone.”

Sleep specialists are equipped to deal with both ordinary, relatively minor problems and less common, more serious cases because of their specific training, familiarity with the various disorders and access to advanced diagnostic techniques, including sleep studies – overnight sessions during which a person’s brain activity, eye movements, heart rate, blood pressure, breathing rate, air flow and other markers are recorded for analysis.

Regardless of its nature, any sleeping problem that lasts more than a few nights shouldn’t be ignored, Kumar advised.

“Even a relatively short-term difficulty with sleeping can develop into a chronic problem if not addressed, and not sleeping properly can have many other health consequences,” she said. “If you think about it, we spend about a third of our lives doing it, so sleeping is extremely important.”